Go-to protein source

This spring, I want to bulk up more. My biggest obstacle in the past has been my diet. I eat fairly healthy, but I don't eat enough for the amount of exercise I do. My metabolism is extremely fast. Even without exercise, it's just genetic. I'm trying to find a good protein source that requires no preparation every three hours. I have some good protein bars, but I don't want to consume so much processed food all the time. I also enjoy tuna in a can/pouch, but I want to avoid excessive mercury exposure. What other easy protein sources do you recommend? I'm not sure if this is on another thread.

you know I had the same issue. I didn't realize that I was burning off too much of my calories working out, that I wasn't eating enough to gain much less then maintain. I know this may sound taboo but, Carbs are your best friend when you want to gain weight. I've been eating a slice or two of rye bread every snack break I get, and brown rice in every major meal. Not only that but always have protein in all my meals whether it's snacking or a major meal. Also I got this protein shake it tastes great but the down side it's super expensive! but I think totally worth it.